Surgical stapling apparatus

ABSTRACT

A surgical stapling apparatus (stapler) is provided. A tool assembly includes first and second jaw members. A cartridge assembly includes an actuation sled and a slide. A drive member having a working end is configured to translate through the tool assembly when the first and second jaw members are in a closed configuration. A lock assembly including a latch is movable from a locked position to an unlocked position. The latch is urged to the locked position to engage the working end to prevent distal translation of the drive member through the tool assembly. The slide is configured to move the latch from the locked position to the unlocked position upon installation of an unspent cartridge assembly onto the first jaw member. The slide is movable by the drive member upon actuation of the stapling apparatus to allow the latch to move back to the locked position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/779,631, filed Mar. 13, 2013, the entiredisclosure of which is incorporated by reference herein.

BACKGROUND

Technical Field

The present disclosure relates to surgical stapling apparatuses. Moreparticularly, the present disclosure relates to surgical staplingapparatuses including working end drive lockout mechanisms.

Description of Related Art

Surgical stapling apparatus configured to staple, and subsequently severtissue are well known in the art. Such stapling apparatuses typicallyinclude a housing or handle and an elongated member that extends fromthe housing. In certain instances, single use or multi use loading unit(MULU) reload may be configured to releasably couple to a distal end ofthe elongated member. In either of the aforementioned reloadconfigurations, a tool assembly including an anvil and a cartridge maybe provided on respective jaws of the reload to staple tissue. The toolassembly can include a knife to sever the stapled tissue. The reload caninclude a drive member having a working end which supports the knife andadvances an actuation sled through the tool assembly to staple and severtissue.

While the aforementioned reload configurations provide numerousadvantages, it may be desirable to prevent inadvertent advancement ofthe drive member of the reload when a staple cartridge is absent fromthe tool assembly or has been fired.

SUMMARY

As can be appreciated, surgical stapling apparatuses that include adrive lockout mechanism may prove useful in the surgical arena.

Embodiments of the present disclosure are described in detail withreference to the drawing figures wherein like reference numeralsidentify similar or identical elements. As used herein, the term“distal” refers to the portion that is being described which is furtherfrom a user, while the term “proximal” refers to the portion that isbeing described which is closer to a user.

An aspect of the instant disclosure provides a surgical staplingapparatus. The surgical stapling apparatus includes a housing and anelongated member therefrom. A tool assembly is supported on a distal endof the elongated member and includes a first jaw member and a second jawmember. A cartridge assembly is releasably supported on the first jawmember and includes an actuation sled and a slide. An anvil is operablysupported on the second jaw member. A drive member having a working endis configured to translate through the tool assembly when the first andsecond jaw members are in a closed configuration. A lock assemblyincluding a latch is movable from a locked position to an unlockedposition. The latch is urged to the locked position to engage theworking end of the drive member to prevent distal translation of thedrive member through the tool assembly. The slide is configured to movethe latch from the locked position to the unlocked position uponinstallation of an unspent cartridge assembly onto the first jaw member.The slide being movable by the drive member upon actuation of thestapling apparatus to allow the latch to move back to the lockedposition.

The lock assembly may be operably coupled to a pivot assembly of thereload. The lock assembly may include a cam pin, at least one resilientmember and at least one washer. The cam pin may be positioned through anaperture defined through the pivot assembly and configured to rotatetherein to move the latch from the locked position to the unlockedposition when contacted by the slide.

The working end may include at least one recess that is configured toselectively engage the latch. The slide may be configured to releasablycouple to the actuation sled. The slide may include at least onemechanical interface that is configured to couple to a correspondingmechanical interface disposed within the cartridge assembly when theactuation sled is moved distally. The mechanical interfaces may bedisposed on the slide deflector and within the cartridge assembly form adovetail joint.

An aspect of the instant disclosure provides a reload. The reloadincludes a tool assembly including a first jaw member and a second jawmember. A cartridge assembly is releasably supported on the first jawmember and includes an actuation sled and a slide. An anvil is operablysupported on the second jaw member. A drive member having a working endis configured to translate through the tool assembly when the first andsecond jaw members are in a closed configuration. A lock assemblyincluding a latch is movable from a locked position to an unlockedposition. The latch is urged to the locked position to engage theworking end of the drive member to prevent distal translation of thedrive member through the tool assembly. The slide is configured to movethe latch from the locked position to the unlocked position uponinstallation of an unspent cartridge assembly onto the first jaw member.The slide is movable by the drive member upon actuation of the staplingapparatus to allow the latch to move back to the locked position.

The lock assembly may be operably coupled to a pivot assembly of thereload. The lock assembly may include a cam pin, at least one resilientmember and at least one washer. The cam pin may be positioned through anaperture defined through the pivot assembly and configured to rotatetherein to move the latch from the locked position to the unlockedposition when contacted by the slide.

The working end may include at least one recess that is configured toselectively engage the latch. The slide may be configured to releasablycouple to the actuation sled. The slide may include at least onemechanical interface that is configured to couple to a correspondingmechanical interface disposed within the cartridge assembly when theactuation sled is moved distally. The mechanical interfaces may bedisposed on the slide deflector and within the cartridge assembly form adovetail joint.

An aspect of the instant disclosure provides a surgical staplingapparatus. The surgical stapling apparatus includes a housing and anelongated member therefrom. A tool assembly is supported on a distal endof the elongated member and includes a first jaw member and a second jawmember. A cartridge assembly is releasably supported on the first jawmember and includes an actuation sled including at least one mechanicalinterface. An anvil is operably supported on the second jaw member andincludes at least one spring and defines a stop. A drive member having aworking end includes at least one mechanical interface. The spring isconfigured to urge the working end of the drive member to position theworking end of the drive member in alignment with the stop on the anvilto prevent the working end of the drive member being advanced distally.The at least one mechanical interface on the actuation sled ispositioned to engage the at least one mechanical interface on theworking end of the drive member to retain the working end of the drivemember out of engagement with the stop to allow advancement of the drivemember through the tool assembly.

The at least one mechanical interface on the actuation sled may be aprotuberance having a slanted configuration that extends proximally andthe at least one mechanical interface on the working end is a recesshaving a configuration that complements the slanted configuration of theprotuberance. The actuation sled may include a detent that may beconfigured to releasably engage a corresponding indent disposed withinthe cartridge assembly.

The spring may be configured to contact a top portion of the working endof the drive member for biasing the working end in the generallydownward direction. The wave spring may be a wave spring.

An aspect of the instant disclosure provides a reload. The reloadincludes a tool assembly including a first jaw member and a second jawmember. A cartridge assembly is releasably supported on the first jawmember and includes an actuation sled including at least one mechanicalinterface. An anvil is operably supported on the second jaw member andincludes at least one spring and defines a stop. A drive member having aworking end includes at least one mechanical interface. The spring isconfigured to urge the working end of the drive member to position theworking end of the drive member in alignment with the stop on the anvilto prevent the working end of the drive member being advanced distally.The at least one mechanical interface on the actuation sled ispositioned to engage the at least one mechanical interface on theworking end of the drive member to retain the working end of the drivemember out of engagement with the stop to allow advancement of the drivemember through the tool assembly.

BRIEF DESCRIPTION OF THE DRAWING

Various embodiments of the present disclosure are described hereinbelowwith references to the drawings, wherein:

FIG. 1 is a side, perspective view of a powered surgical staplingapparatus supporting a reload;

FIG. 2 is a side, perspective view of a manual surgical staplingapparatus supporting a reload;

FIG. 3A is a side perspective view of the reload of FIGS. 1 and 2including a drive lockout mechanism according to an embodiment of theinstant disclosure;

FIG. 3B is a side, perspective view of a tool assembly of the reloadshown in FIGS. 1-3A;

FIG. 4 is an enlarged view of the indicated area of detail of FIG. 3C;

FIG. 5 is an exploded view of the pivot assembly shown in FIG. 4 and adrive member including a working end of the reload shown separated fromone another;

FIG. 6 is a perspective view of the cam pin shown in FIG. 5;

FIG. 7 is a partial, cross-sectional view taken along line portion 7 inFIG. 4;

FIG. 8 is a side, perspective view of the pivot assembly depicted inFIG. 4 shown inverted;

FIG. 9 perspective view of the cartridge assembly and jaw shown in FIG.3B separated from one another and with an actuation and slide of thecartridge assembly separated from the cartridge assembly;

FIG. 10 is a cross-sectional view taken along line portion 10 in FIG. 9;

FIG. 11 is a partial, perspective view of a proximal end of thecartridge assembly with the slide removed to show a guide of thecartridge assembly;

FIG. 12 is a partial, perspective view of the proximal end of thecartridge assembly with the slide shown coupled to the guide providedshown in FIG. 11;

FIG. 13 is a partial, perspective view of the proximal end of the toolassembly shown in FIG. 3B illustrating a top portion of the pivotassembly shown in FIG. 4 with the cartridge assembly installed on thejaw member and the working end of the reload is in a pre-advancedposition;

FIG. 14 is a partial, perspective view of the proximal end of the toolassembly shown in FIG. 3B illustrating a bottom portion of the pivotassembly shown in FIG. 4 with the cartridge assembly installed on thejaw member and the working end of the reload in a pre-advanced position;

FIG. 15 is a side, cross-sectional view of a tool assembly of a reloadincluding a drive lockout mechanism according to an alternate embodimentof the instant disclosure and with a working end in a retractedposition;

FIG. 16 is a partial, cross-sectional view of the tool assembly with theworking end of the reload being advanced distally towards an actuationsled of a cartridge assembly of the reload;

FIG. 17 is a partial, cross-sectional view of the tool assembly with theworking end of the reload engaged with the actuation sled and with theworking end positioned for further advancement thereof through thereload;

FIG. 18 is a partial, cross-sectional view of the tool assembly with theworking end engaged with the actuation sled and being translated throughcartridge assembly; and

FIG. 19 is a partial, cross-sectional view of the tool assembly with theworking end in the retracted position.

DETAILED DESCRIPTION

Detailed embodiments of the present disclosure are disclosed herein;however, the disclosed embodiments are merely examples of thedisclosure, which may be embodied in various forms. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as arepresentative basis for teaching one skilled in the art to variouslyemploy the present disclosure in virtually any appropriately detailedstructure.

In accordance with the instant disclosure, various drive lockoutmechanisms are disclosed herein and are configured for use with surgicalstapling apparatus adapted to receive replaceable staple cartridge. Thevarious drive lockout mechanisms described below are configured toprevent firing of the surgical stapling apparatus prior to installing acartridge, or including a spent or empty cartridge installed.

FIG. 1 illustrates a powered surgical stapling apparatus shown generallyas 100. FIG. 2 illustrates a manual surgical stapling apparatus showngenerally as 200. The powered apparatus includes one or more motors andan internal or external power source for mechanically actuating thestapling apparatus, whereas the manual apparatus 200 has a movablehandle 236 for manually actuating the stapling apparatus. See U.S. Pat.Nos. 5,865,361; 5,782,396; International WO 04/032,760; U.S. PatentPublication No. 2010/0276741; and U.S. patent application Ser. No.13/444,228, the entire contents of each of these disclosures is herebyincorporated herein by reference.

Briefly, the surgical stapling apparatus 100 includes a housing orstationary handle 102 having an actuator 136 and an elongated member 104extending from housing 102 (FIG. 1). Likewise, surgical staplingapparatus 200 includes a housing or stationary handle 202 supporting amovable handle 236 and an elongated member 204 extending from housing202. Surgical stapling apparatus 200 includes a retraction mechanism 217(FIG. 2) that can be manually grasped and pulled proximally to retract afiring mechanism of the apparatus 200. Each of elongated members 104,204 is configured to removably couple to a reload 106. Although theembodiments described herein disclose a reload 106 including a toolassembly 107 which is releasably coupled to the elongate member 104,204, it is envisioned that the tool assembly can be fixedly secured tothe distal end of the elongated member 104, 204.

Referring to FIG. 3A, the reload 106 includes a shaft portion 109 and atool assembly 107 supported on a distal end of the shaft portion 109.The tool assembly 107 includes first and second jaw members 108, 110which are movable from a spaced apart configuration (FIG. 2) forpositioning tissue therebetween to an approximated configuration (notshown) for clamping tissue and subsequently stapling tissue. Jaw member108 releasably supports a cartridge assembly 112 and jaw member 110supports an anvil 111 that includes a plurality of buckets ordepressions 120 that are configured to receive corresponding fasteners(not shown) when the fasteners are deployed from the cartridge 112.

Reference may be made to U.S. Pat. Nos. 5,865,361 and 7,225,963, theentire contents of which are incorporated herein by reference, for amore detailed discussion of the construction and operation of reload106.

FIG. 3B illustrates the tool assembly 107 of the reload with the jawmembers 108, 110 in an approximated configuration and with cartridge 112separated from the jaw member 108. The reload 106 includes a lockingmechanism that is configured to lock-out a drive member “D” (FIG. 5) soas to prevent firing of the apparatus when a cartridge 112 has not beeninstalled in the jaw member 108 or when the cartridge 112 installed injaw member 108 has already been fired.

A pivot assembly 150 (FIG. 3B) is provided at a distal end of shaft 109which pivotally couples tool assembly 107 to shaft 109. Referring toFIGS. 4-5, pivot assembly 150 includes top and bottom portions 151 a,151 b that are operably coupled to one another and to jaw members 108,110, respectively, so as to allow articulation of jaw members 108, 110(FIG. 3B) about an axis transverse to the longitudinal axis of thereload 106. Bottom portion 151 b of pivot assembly 150 is configured tooperably support a lock assembly 130 that is operable to preventadvancement of the working end 101 of drive member “D” distally when thecartridge 112 has been fired or is absent from the jaw member 108.Specifically, bottom portion 151 b includes a pair of distally extendingleg members 153 a, 153 b. Leg members 153 a, 153 b are spaced-apart fromone another to receive a drive beam 103 of drive member “D” therebetween(FIGS. 4-5 and 7-8) so as to allow advancement of working end 101 thoughthe cartridge 112, as will be described in greater detail below. Legmembers 153 a, 153 b include a generally elongated configuration. In theillustrated embodiment, leg member 153 b is slightly longer than legmember 153 a and includes a distal end having a generally arcuateconfiguration. While leg member 153 b is illustrated having a lengththat is greater than a length of leg member 153 a, it is within thepurview of the present disclosure to provide leg members 153 a, 153 bwith the same length.

An aperture 155 extends through a distal end of leg member 153 b toreceive a cam pin 134 of lock assembly 130. A notch 156 is provided onleg member 153 b adjacent aperture 155 and is positioned to receive acam feature 144 of cam pin 134 to allow rotation of the cam pin 134within aperture 155, as will be described in greater detail below.

Referring to FIGS. 4-8, lock assembly 130 includes a latch 132, cam pin134 and a spring clip 131. Cam pin 134 is configured to rotate withinaperture 155 as cartridge 112 is being installed on jaw member 108 inresponse to engagement with slide 160. To this end, cam pin 134 includesa generally elongated configuration including an upper portion 135having a non circular configuration that is configured to benon-rotatably received within a corresponding aperture 137 that isdefined through latch 132. As such, rotation of cam pin 134 causescorresponding rotation of latch 132 between locked (FIG. 7) and unlockedpositions. A shelf 139 (FIG. 6) is provided on cam pin 134 adjacent topportion 135 and aligns with a top, planar surface of leg member 153 bwhen cam pin 134 is seated within aperture 155. In embodiments, forexample, shelf 139 may be utilized to help support latch 132 and/orraise latch 132 off of the top surface of leg member 153 b.

Cam pin 134 includes a base 140 having a flange portion 138 that engagesa bottom portion of leg member 153 b adjacent notched portion 156 whencam pin 134 is seated within aperture 155 of leg member 153 b. Flangeportion 138 is provided adjacent base 140 and extends partially along anouter circumferential surface of cam pin 134. Flange 138 includes a camfeature 144 that is configured to engage a cam extension 162 disposed ona slide 160 (FIG. 9) that is releasably coupled to an actuation sled 115of cartridge 112 when cartridge 112 is being installed on jaw member108, as will be described in greater detail below.

A top surface 146 of flange portion 138 is generally planar and ispositioned to abut a bottom surface of leg member 153 b such that camfeature 144 is disposed within notch 156 of leg member 133 b when campin 134 is positioned through aperture 155 (as best seen in FIG. 8). Camfeature 144 is movable within the recess 156 as to allow rotation of campin 134 within aperture 155 when cartridge 112 is being installed andwhen working end 101 of drive member “D” is returned to the retractedposition. Cam pin 134 is rotatable within aperture 155 from a positionin which latch 132 obstructs movement of the drive member “D” (FIG. 7)to a position in which latch 132 is spaced from drive member “D,” aswill be discussed in further detail below.

A protrusion 148 is provided on base 140 of cam pin 134 and is receivedbetween spaced-apart resilient leg portions 133 a, 133 b of spring clip131 (as best seen in FIG. 8). Protrusion 148 is positioned between theleg portions 133 a, 133 b such that rotation of cam pin 134 withinaperture 155 causes resilient leg portions 133 a, 133 b deflectoutwardly (FIG. 13). Leg portions 133 a, 133 b are configured to contactprotrusion 148 to retain cam pin 134 and, thus, latch 132 in the lockedposition, as shown in FIG. 7. In the locked position, latch 132 ispositioned to engage a recess 116 provided on working end 101 of drivemember “D” (FIG. 5) to prevent distal advancement of drive member “D.”In the locked position, protrusion 148 extends parallel to and betweenleg portions 133 a, 133 b (FIG. 8) and the leg portions 133 a, 133 b areunbiased. When cartridge 112 is installed in jaw member 108, camextension 162 of slide 160 contacts cam feature 144 and moves camfeature 144 proximally, which, in turn, rotates cam pin 134 and, thus,rotates protrusion 148 into contact with leg portions 133 a, 133 b (FIG.13) to deflect leg portions 133 a, 133 b of spring clip 131 outwardly.As a result thereof, latch 132 is rotated out of engagement with recess116 of working end 101 to facilitate distal advancement of the drivemember “D.” Cam extension 162 of slide 160 remains engaged with camfeature 144 of cam pin 134 until such time that working end 101 isadvanced and caused to engage actuation sled 115. When this occurs,movement of cam extension 162 out of engagement with cam feature 144allows protrusion 148 to return to the locked out configuration as aresult of the biasing force provided by leg portions 133 a, 133 b ofspring clip 131 on protrusion 148.

Leg portions 133 a, 133 b of spring clip 131 meet at a generally arcuateproximal end 133 c of spring clip 131 (FIG. 5). The arcuateconfiguration of proximal end 133 c provides a suitable spring constantthat allows leg portions 133 a, 133 b to bias the protrusion 148 suchthat the latch 132 is moved to the locked position when slide 160 isdisengaged from cam feature 144 of cam pin 134.

An aperture 133 d of spring clip 131 is provided adjacent proximal end133 c and is configured to receive a corresponding rivet 154 (or othersuitable device) that is provided on a bottom portion 151 b of pivotassembly 150 (FIGS. 5 and 8). A washer 158 may be utilized to couple torivet 154 for securing lock assembly 130 to bottom portion 151 b.

Latch 132 is configured to prevent distal advancement of working end 101of drive member “D” when the latch 132 is in a locked position. Latch132 includes an end 145 a that defines the aperture 137. A generallyelongated member 145 b extends from end 145 a and includes a tip 145 cthat is configured to be releasably received within recess 116 (FIG. 7)of working end 101 of the drive member “D.”

With reference again to FIG. 5, drive member “D” includes a drive beam103 which supports the working end 101. Working end 101 has an I-beamconfiguration having top and bottom flanges 118 a, 118 b and includes adistal abutment surface 118 c which engages a central support wedge 113a (FIG. 9) of the actuation sled 115 (FIG. 9). Working end 101 isconfigured to move through the tool assembly 107 which includes knifechannel portions 114 a (FIG. 3A), 114 b (FIG. 9) that are definedthrough an anvil 111 which is supported on the jaw member 110 and jawmember 108, respectively. Specifically, the working end 101 of the drivebeam 103 moves from a retracted position to an extended position toadvance the working end 101 and the actuation sled 115 through acartridge 112 to staple and sever tissue. The knife 105 is positioned totravel slightly behind the actuation sled 115 during a staplingprocedure to form an incision between the rows of stapled tissue.

The recess 116 is provided at a proximal end of working end 101 of drivemember “D” adjacent top flange 118 a and is defined by a sidewall 119 aand a back wall 119 b. Sidewall 119 a is angled and extends distallyfrom back wall 119 b. The recess 116 is configured to slidably receivedistal tip 145 c of elongated member 145 b and guide distal tip 145 ctowards back wall 119 b to lock out working end 101, as best seen inFIG. 7.

In accordance with the instant disclosure, prior to installing cartridge112 onto jaw member 108, working end 101 of drive member “D” isretracted and in the locked out position. More specifically, legportions 133 a, 133 b of spring clip 131 are positioned to retainprotrusion 148 of cam pin 134 at an orientation to position latch 132 inthe locked put position (FIG. 7). In order to move the latch 132 fromthe locked position, an unfired cartridge 112 must be installed on jawmember 108 as discussed below.

With reference to FIGS. 9-14, jaw member 108 of tool assembly 107 isconfigured to support removable cartridge assembly 112 thereon.Cartridge 112 includes the plurality of fasteners and a plurality ofpusher members (not shown) that are operatively engaged with thefasteners. Cartridge 112 also includes one or more retention slots 119that are positioned longitudinally along a tissue contacting surface 121of cartridge 112 and are configured to house a plurality of fasteners(not shown). A cartridge housing 123 (FIG. 9) is coupled to jaw member108. In any of the embodiments disclosed herein, cartridge 112 may becoupled to jaw 108 using detents 125 (FIG. 9), latches, clips or thelike. A removable and replaceable cartridge is disclosed in U.S. patentapplication Ser. No. 13/280,880 entitled Multi-Use Loading Unit, theentire disclosure of which is hereby incorporated by reference herein.

An actuation sled 115 is positioned at a proximal end of cartridge 112and is held in place within cartridge 112 via an indent/detentconfiguration. Specifically, an indent 164 a is provided on a sidesurface 165 of a central wedge support 113 a and engages a correspondingdetent 164 b that is provided on a left interior side wall 149 c ofcartridge 112 (FIG. 10). Detent 164 b is configured to release fromindent 164 a when working end 101 of drive member “D” contacts actuationsled 115 and is advanced distally through cartridge 112.

Slide 160 has a generally elongated configuration with proximal anddistal ends 163 a, 163 b. The cam extension 162 (a generally elongatedprotrusion, detent or the like) is provided at the proximal end 163 a ofslide 160 and is positioned on actuation sled 115 to engage the camfeature 144 of lockout assembly 130 to rotate latch 132 into theunlocked position when cartridge 112 is being coupled to jaw member 108(FIGS. 12-13).

Slide 160 is supported between raised wedge supports of the actuationsled 115 to releasably couple the slide 160 to the actuation sled 115.Specifically, slide 160 is coupled to actuation sled 115 between thecentral wedge support 113 a and a right wedge support 113 b of actuationsled 115 (FIG. 9). More specifically, slide 160 releasably couples toactuation sled 115 via a resilient member in the form of a spring 172(band, coil or the like) having proximal and distal ends 175 a, 175 b.Proximal end 175 a of spring 172 is configured to bias proximal end 163a of the slide 160 against a proximal end of the right support wedge 113b such that slide 160 remains coupled to actuation sled 115 as cartridge112 is being installed onto jaw member 108 and cam extension 162 engagescam feature 144 to move latch 132 out of engagement with recess 116 ofworking end 101 of the drive member “D.” Spring 172 may also be utilizedto facilitate biasing detent 164 b of cartridge 112 into engagement withindent 164 a of actuation sled 115. Spring 172 is press or friction fitinto a pair of corresponding recesses 174 a, 174 b that are provided ona sidewall 166. Specifically, recess 174 b is disposed distal of recess174 a and is configured to receive the distal end 175 b of spring 172.The proximal end 175 a of spring 172 is received within recess 174 a.

Sidewall 166 of slide 160 defines a groove 167 configured to receive acorresponding guide member 168 which extends from a right interiorsidewall 169 b of cartridge 112 (FIG. 11). Right interior sidewall 169 bincluding guide member 168 is positioned within cartridge 112 to allowdistal translation of actuation sled 115 through cartridge 112. In oneembodiment, groove 167 has a dovetail configuration and receives theguide member 168 of corresponding shape.

Referring to FIGS. 11-12, in accordance with the instant disclosure,when working end 101 of drive member “D” is advanced to contact andadvance the actuation sled 115, working end 101 and actuation sled 115including slide 160 initially move distally in unison (spring 172maintains slide 160 and actuation sled coupled to one another).Continued distal translation of the working end 101 of the drive member“D” causes groove 167 to receive guide member 168. Guide member 168guides slide 160 into engagement with an interior wall 169 a ofcartridge 112 (FIGS. 11-12) adjacent right interior sidewall 169 b toprevent further distal movement of the slide 160. When distal end 163 bof the slide 160 contacts interior wall 169 a, slide 160 disengages fromactuation sled 115. With groove 167 engaged with guide member 168, slide160 is secured to interior sidewall 169 b and prevented from furthermovement within cartridge 112. As such, when working end 101 of drivemember “D” is moved back to the retracted configuration, the slide 160is retained in the advanced position with the distal end 163 b incontact with interior wall 169 a.

In use, when a cartridge assembly 112 is not installed on jaw member108, latch 132 is in a locked configuration with distal tip 145 c oflatch 132 positioned within recess 116 of working end 101 (FIG. 7). Withdistal tip 145 c of latch 132 in this configuration, as the drive member“D” is advanced distally, engagement between distal tip 145 c and backwall 119 b of recess 116 prevents further advancement of drive member“D” (drive member “D” is locked out) (FIGS. 7-8).

When the cartridge 112 is installed in jaw member 108, cam extension 162of slide 160 contacts cam feature 144 of cam pin 134 to rotate cam pin134 within aperture 155. Rotation of cam pin 134 effects correspondingrotation of latch 132 to move latch 132 out of engagement with recess116 of working end 101. In this position, protrusion 148 of cam pin 134deflects leg portions 133 a, 133 b of spring clip 131 outwardly suchthat leg portions 133 a, 133 b of spring clip 131 urge cam pin 134 backto a position in which the latch 132 is in the locked position asdescribed above, see FIGS. 13-14 for example. Moreover, slide 160 ismaintained coupled to actuation sled 115 in a manner as described above.

With latch 132 and slide 160 in the pre-fired configuration, drivemember “D” including working end 101 is allowed to translate distallypast the distal tip 145 c of the latch 132 and engage actuation sled 115in a manner as described above. Distal translation of slide 160 movescam extension 162 of slide 160 out of engagement with cam feature 144and allows latch 132 to move back to the locked-out configuration viathe biasing force provided by leg portions 133 a, 133 b of the springclip 131.

After the cartridge 112 has been fired, refraction of the drive member“D” will cause working end 101 to engage and pivot the latch 132 out ofthe path of the working end 101 such that drive member “D” will moveproximally past latch 132 until working end 101 of the drive member “D”returns to the retracted configuration. In the retracted configuration,latch 132 is engaged within recess 116 such that distal tip 145 c oflatch 132 is positioned to engage back wall 119 b of recess 116 toprevent further advancement of drive member “D,” as described above.

The unique configuration of lock assembly 130 overcomes theaforementioned drawbacks that are, typically, associated withconventional surgical stapling apparatus. Specifically, lock assembly130 prevents firing of a surgical stapling apparatus which does not havea cartridge 112 installed, or firing of a surgical stapling apparatuswith a spent or empty cartridge 112 installed.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same.

For example, with reference to FIGS. 15-19, an alternate embodiment oflocking mechanism is illustrated. Accordingly, only those features thatare unique to the embodiment illustrated in FIGS. 15-19 are describedherein.

An anvil 211 includes a stop in the form of a notch 219 at a proximalend thereof that is configured to lock out a working end 201 of thedrive member “D.” Specifically, notch 219 is configured to engage a topflange 218 a of working end 201 of the drive member “D” to preventworking end 201 from translating distally past notch 219.

A resilient member in the form of a wave spring 231 (or other suitablespring, e.g., coil, torsion, etc.) is operably coupled (e.g., via laseror electron welding) to an upper interior surface 223 of the jaw member210. One or more other suitable coupling methods may also be utilized tocouple spring 231 to interior surface 223. For example, adhesives,various mechanical interfaces and the like may be utilized to couplespring 231 to interior surface 223. Spring 231 is positioned proximal ofnotch 219 and is configured to contact a top flange 218 a of working end201 to bias flange 218 a in a generally downwardly direction.Specifically, spring 231 biases top flange 218 a into alignment withnotch 219 such that distal translation of the working end 201 of thedrive member “D” causes top flange 218 a of working end 201 to engagethe notch 219 on the anvil 211 to prevent further advancement of thedrive member “D.” In a compressed configuration, top flange 218 a of theknife 205 will be positioned above notch 219 to allow furtheradvancement of the drive member “D” through the cartridge.

A recess 216 is provided at a distal end of working end 201 adjacent abottom flange 218 b. Specifically, recess 216 is defined by a back wall220 of working end 201 having a slanted configuration and is configuredengage a corresponding protuberance in the form of a ramp 260 providedat a proximal end of the actuation sled 215. Engagement between recess216 and ramp 260 raises top flange 218 a above notch 219 against thebiasing force of spring 231 to allow distal translation of working end201 of the drive member “D” past notch 219.

Unlike actuation sled 115, actuation sled 215 is not configured tocouple to a slide 160. Rather, ramp 260 extends proximally from theproximal end of actuation sled 215 and is positioned to engage back wall220 of recess 216 when working end 201 of the drive member “D” istranslated distally.

An indent/detent configuration (or other suitable mechanical interface)may be utilized to maintain actuation sled 215 in place while cartridge212 is being installed on the jaw member (not shown for claritypurposes). In the embodiment illustrated in FIGS. 15-19, for example, anindent 240 (FIGS. 18-19) is provided on an interior bottom surface 242of cartridge 212 and a corresponding detent 244 is provided on a bottomsurface 246 of actuation sled 215 (FIGS. 15-17). Once knife 205 of theworking end 201 contacts actuation sled 215, detent 244 releases fromindent 240 and slides along interior bottom surface 242 with actuationsled 215.

In use, when cartridge assembly 212 is not installed on the jaw member,spring 231 is in a uncompressed state and configured to bias top flange218 a of the knife 205 in a manner as described above. With top flange218 a in the biased configuration, working end 201 of the drive member“D” is locked out and prevented from misfiring.

When cartridge 212 is installed on the jaw member, ramp 260 ispositioned to engage recess 216 (FIGS. 15-16). Specifically, when thedrive member “D” is advanced, ramp 260 of actuation sled 215 engagesback wall 220 of recess 216 and raises top flange 218 a of knife 205above notch 219 on anvil 211 (FIG. 17) against the biasing forceprovided by spring 231. Spring 231 will remain in the compressed stateuntil such time that ramp 260 is disengaged from recess 216. As a resultthereof, drive member “D” is allowed to translate distally throughcartridge 212 to staple and severe the stapled tissue (FIG. 18). Oncetop flange 218 a of the working end 201 translates distally past notch219, spring 231 will move back to the uncompressed configuration.

Working end 201 of the drive member “D” may then be moved proximallyback to the retracted configuration. With the working end 201 in theretracted configuration, spring 231 will be in the uncompressed statefor biasing top flange 218 a of the knife 205 in a manner as describedabove to lock out the drive member “D” working end 201 and preventfiring of a surgical stapling apparatus which does not have a cartridge212 installed, or firing of a surgical stapling apparatus with a spentor empty cartridge 112 installed.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

What is claimed is:
 1. A surgical stapling apparatus, comprising: ahousing; an elongated member extending from the housing; a tool assemblysupported on a distal end of the elongated member, the tool assemblyincluding a first jaw member and a second jaw member configured to moverelative to each other between an open configuration and a closedconfiguration; a cartridge assembly including a plurality of staples,the cartridge assembly releasably supported on the first jaw member, thecartridge assembly including an actuation sled and a slide releasablycoupled to the actuation sled; an anvil operably supported on the secondjaw member; a drive member having a working end that is positioned andconfigured to translate through the first and second jaw members of thetool assembly when the first and second jaw members are in the closedconfiguration, the drive member being movable independently of theslide; a lock assembly including a latch movable from a locked positionto an unlocked position, wherein in the locked position, the latch ispositioned and configured to prevent distal translation of the drivemember through the tool assembly; and a spring member positioned andconfigured to urge the latch towards the locked position wherein theslide is configured to move the latch from the locked position to theunlocked position upon installation of the cartridge assembly onto thefirst jaw member, the drive member moving the slide and the actuationsled distally upon actuation of the stapling apparatus, and in a distalconfiguration of the slide, the slide uncouples from the actuation sledand the spring member biases the latch to move to the locked position.2. A surgical stapling apparatus according to claim 1, further includinga pivot assembly, wherein the lock assembly is operably coupled to thepivot assembly.
 3. A surgical stapling apparatus according to claim 2,wherein the lock assembly includes a cam pin configured to be contactedby the slide, the resilient member and at least one washer, and whereinthe cam pin is positioned through an aperture defined through the pivotassembly, the cam pin being configured to rotate within the aperture tomove the latch from the locked position to the unlocked position whenthe cam pin is contacted by the slide.
 4. A surgical stapling apparatusaccording to claim 3, wherein the working end includes at least onerecess that is configured to selectively engage the latch.
 5. A surgicalstapling apparatus according to claim 1, wherein the slide is configuredto releasably couple to the actuation sled.
 6. A surgical staplingapparatus according to claim 1, wherein the slide includes at least onemechanical interface that is configured to couple to a correspondingmechanical interface disposed within the cartridge assembly when theactuation sled is moved distally.
 7. A surgical stapling apparatusaccording to claim 6, wherein the mechanical interfaces disposed on theslide and within the cartridge assembly form a dovetail joint.
 8. Areload comprising: a tool assembly including a first jaw member and asecond jaw member configured to move relative to each other between anopen configuration and a closed configuration; a cartridge assemblyreleasably supported on the first jaw member, the cartridge assemblyincluding an actuation sled and a slide releasably coupled to theactuation sled; an anvil supported on the second jaw member; a drivemember having a working end configured to translate through the toolassembly when the first and second jaw members are in the closedconfiguration; and a lock assembly including a latch movable from alocked position to an unlocked position, wherein in the locked position,the latch is positioned and configured to prevent distal translation ofthe drive member through the reload, wherein the slide is configured tomove the latch from the locked position to the unlocked position uponinstallation of the cartridge assembly onto the first jaw member, theslide being coupled to the actuation sled during installation of thecartridge assembly.
 9. A reload according to claim 8, wherein the lockassembly is operably coupled to a pivot assembly of the reload.
 10. Areload according to claim 9, wherein the lock assembly includes a campin configured to be contacted by the slide, at least one resilientmember and at least one washer, and wherein the cam pin is positionedthrough an aperture defined through the pivot assembly, the cam pinbeing configured to rotate within the aperture to move the latch fromthe locked position to the unlocked position when the cam pin iscontacted by the slide.
 11. A reload according to claim 10, wherein theworking end includes at least one recess that is configured toselectively engage the latch.
 12. A reload according to claim 8, whereinthe slide is configured to releasably couple to the actuation sled. 13.A reload according to claim 8, wherein the slide includes at least onemechanical interface that is configured to couple to a correspondingmechanical interface disposed within the cartridge assembly when theactuation sled is moved distally.
 14. A reload according to claim 13,wherein the mechanical interfaces disposed on the slide and within thecartridge assembly form a dovetail joint.